Well, I like my candles to leave no wax on the sides of the jar when burning. However, this won't happen if not burned properly. Ideally, a candle should burn, if wicked correctly, with a melt pool of about an inch per hour. So, a three inch round container should reach a full melt pool in three hours or so. If someone doesn't burn the candle long enough, it will have excess wax on the edge. I don't like smokey wicks either. Nobody wants soot from their candles. So, it does require a lot of testing to get the best wick, wax, fragrance and container combo. Of course, you must be aware that I am a perfectionist about the performance of my candles.